AlKhatib Zainab, Lagedroste Marcel, Zaschke Julia, Wagner Manuel, Abts André, Fey Iris, Kleinschrodt Diana, Smits Sander H J
Institute of Biochemistry, Heinrich Heine University Duesseldorf, Universitaetsstrasse 1, 40225, Duesseldorf, Germany.
Microbiologyopen. 2014 Oct;3(5):752-63. doi: 10.1002/mbo3.205. Epub 2014 Aug 30.
The lantibiotic nisin is a small 3.4 kDa antimicrobial peptide, which acts against Gram-positive bacteria in the nmol/L range. Nisin is produced and secreted by several Lactococcus lactis strains to ensure advantages against other bacteria in their habitat. Nisin contains five specific lanthionine rings of which the first two are important for Lipid II binding and the last two are crucial for the pore formation in the membrane. To gain immunity against nisin, the producing strain is expressing an ABC transporter called NisFEG, which expels nisin from the membrane. As a result six to eightfold more nisin is needed to affect the cells. The hydrolysis of ATP by NisFEG is required for this immunity as shown by a mutant, where the ATP hydrolysis is disrupted (NisFH181A EG). Furthermore, NisFEG recognizes the C-terminus of nisin, since deletion of the last six amino acids as well as of the last ring lowered the fold of immunity displayed by NisFEG.
羊毛硫抗生素乳链菌肽是一种分子量为3.4 kDa的小抗菌肽，在纳摩尔/升范围内对革兰氏阳性菌起作用。几种乳酸乳球菌菌株产生并分泌乳链菌肽，以确保在其生存环境中相对于其他细菌具有优势。乳链菌肽含有五个特定的羊毛硫氨酸环，其中前两个对脂质II结合很重要，后两个对膜孔形成至关重要。为了获得对乳链菌肽的免疫，产生菌株表达一种名为NisFEG的ABC转运蛋白，该转运蛋白将乳链菌肽从膜中排出。因此，影响细胞需要多六至八倍的乳链菌肽。如一个ATP水解被破坏的突变体（NisFH181A EG）所示，NisFEG的ATP水解对于这种免疫是必需的。此外，NisFEG识别乳链菌肽的C末端，因为删除最后六个氨基酸以及最后一个环会降低NisFEG显示的免疫倍数。
